[SPARC64]: Sun4v cross-call sending support.

Technically the hypervisor call supports sending in a list
of all cpus to get the cross-call, but I only pass in one
cpu at a time for now.

The multi-cpu support is there, just ifdef'd out so it's easy to
enable or delete it later.

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 163 insertions, 4 deletions

diff --git a/arch/sparc64/kernel/irq.c b/arch/sparc64/kernel/irq.c
index ff201c007e0c..c80d2531ec46 100644
--- a/arch/sparc64/kernel/irq.c
+++ b/arch/sparc64/kernel/irq.c
@@ -900,6 +900,24 @@ static void __cpuinit init_one_kbuf(unsigned long *pa_ptr)
         *pa_ptr = __pa(page);
 }
 
+static void __cpuinit init_cpu_send_mondo_info(struct trap_per_cpu *tb)
+{
+#ifdef CONFIG_SMP
+        unsigned long page;
+
+        BUILD_BUG_ON((NR_CPUS * sizeof(u16)) > (PAGE_SIZE - 64));
+
+        page = get_zeroed_page(GFP_ATOMIC);
+        if (!page) {
+                prom_printf("SUN4V: Error, cannot allocate cpu mondo page.\n");
+                prom_halt();
+        }
+
+        tb->cpu_mondo_block_pa = __pa(page);
+        tb->cpu_list_pa = __pa(page + 64);
+#endif
+}
+
 /* Allocate and init the mondo and error queues for this cpu.  */
 void __cpuinit sun4v_init_mondo_queues(void)
 {
@@ -908,10 +926,14 @@ void __cpuinit sun4v_init_mondo_queues(void)
 
         init_one_mondo(&tb->cpu_mondo_pa, HV_CPU_QUEUE_CPU_MONDO);
         init_one_mondo(&tb->dev_mondo_pa, HV_CPU_QUEUE_DEVICE_MONDO);
+
         init_one_mondo(&tb->resum_mondo_pa, HV_CPU_QUEUE_RES_ERROR);
         init_one_kbuf(&tb->resum_kernel_buf_pa);
+
         init_one_mondo(&tb->nonresum_mondo_pa, HV_CPU_QUEUE_NONRES_ERROR);
         init_one_kbuf(&tb->nonresum_kernel_buf_pa);
+
+        init_cpu_send_mondo_info(tb);
 }
 
 /* Only invoked on boot processor. */
diff --git a/arch/sparc64/kernel/smp.c b/arch/sparc64/kernel/smp.c
index 223cc6bd369a..c10a3a8639e8 100644
--- a/arch/sparc64/kernel/smp.c
+++ b/arch/sparc64/kernel/smp.c
@@ -531,10 +531,133 @@ retry:
         }
 }
 
+#if 0
+/* Multi-cpu list version.  */
+static int init_cpu_list(u16 *list, cpumask_t mask)
+{
+        int i, cnt;
+
+        cnt = 0;
+        for_each_cpu_mask(i, mask)
+                list[cnt++] = i;
+
+        return cnt;
+}
+
+static int update_cpu_list(u16 *list, int orig_cnt, cpumask_t mask)
+{
+        int i;
+
+        for (i = 0; i < orig_cnt; i++) {
+                if (list[i] == 0xffff)
+                        cpu_clear(i, mask);
+        }
+
+        return init_cpu_list(list, mask);
+}
+
+static void hypervisor_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
+{
+        int this_cpu = get_cpu();
+        struct trap_per_cpu *tb = &trap_block[this_cpu];
+        u64 *mondo = __va(tb->cpu_mondo_block_pa);
+        u16 *cpu_list = __va(tb->cpu_list_pa);
+        int cnt, retries;
+
+        mondo[0] = data0;
+        mondo[1] = data1;
+        mondo[2] = data2;
+        wmb();
+
+        retries = 0;
+        cnt = init_cpu_list(cpu_list, mask);
+        do {
+                register unsigned long func __asm__("%o0");
+                register unsigned long arg0 __asm__("%o1");
+                register unsigned long arg1 __asm__("%o2");
+                register unsigned long arg2 __asm__("%o3");
+
+                func = HV_FAST_CPU_MONDO_SEND;
+                arg0 = cnt;
+                arg1 = tb->cpu_list_pa;
+                arg2 = tb->cpu_mondo_block_pa;
+
+                __asm__ __volatile__("ta        %8"
+                                     : "=&r" (func), "=&r" (arg0),
+                                       "=&r" (arg1), "=&r" (arg2)
+                                     : "0" (func), "1" (arg0),
+                                       "2" (arg1), "3" (arg2),
+                                       "i" (HV_FAST_TRAP)
+                                     : "memory");
+                if (likely(func == HV_EOK))
+                        break;
+
+                if (unlikely(++retries > 100)) {
+                        printk("CPU[%d]: sun4v mondo error %lu\n",
+                               this_cpu, func);
+                        break;
+                }
+
+                cnt = update_cpu_list(cpu_list, cnt, mask);
+
+                udelay(2 * cnt);
+        } while (1);
+
+        put_cpu();
+}
+#else
+/* Single-cpu list version.  */
 static void hypervisor_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
 {
-        /* XXX implement me */
+        int this_cpu = get_cpu();
+        struct trap_per_cpu *tb = &trap_block[this_cpu];
+        u64 *mondo = __va(tb->cpu_mondo_block_pa);
+        u16 *cpu_list = __va(tb->cpu_list_pa);
+        int i;
+
+        mondo[0] = data0;
+        mondo[1] = data1;
+        mondo[2] = data2;
+        wmb();
+
+        for_each_cpu_mask(i, mask) {
+                int retries = 0;
+
+                do {
+                        register unsigned long func __asm__("%o0");
+                        register unsigned long arg0 __asm__("%o1");
+                        register unsigned long arg1 __asm__("%o2");
+                        register unsigned long arg2 __asm__("%o3");
+
+                        cpu_list[0] = i;
+                        func = HV_FAST_CPU_MONDO_SEND;
+                        arg0 = 1;
+                        arg1 = tb->cpu_list_pa;
+                        arg2 = tb->cpu_mondo_block_pa;
+
+                        __asm__ __volatile__("ta        %8"
+                                             : "=&r" (func), "=&r" (arg0),
+                                               "=&r" (arg1), "=&r" (arg2)
+                                             : "0" (func), "1" (arg0),
+                                               "2" (arg1), "3" (arg2),
+                                               "i" (HV_FAST_TRAP)
+                                             : "memory");
+                        if (likely(func == HV_EOK))
+                                break;
+
+                        if (unlikely(++retries > 100)) {
+                                printk("CPU[%d]: sun4v mondo error %lu\n",
+                                       this_cpu, func);
+                                break;
+                        }
+
+                        udelay(2 * i);
+                } while (1);
+        }
+
+        put_cpu();
 }
+#endif
 
 /* Send cross call to all processors mentioned in MASK
  * except self.
diff --git a/arch/sparc64/kernel/traps.c b/arch/sparc64/kernel/traps.c
index 5417ff1b9345..ac171161e794 100644
--- a/arch/sparc64/kernel/traps.c
+++ b/arch/sparc64/kernel/traps.c
@@ -2377,7 +2377,11 @@ void __init trap_init(void)
             (TRAP_PER_CPU_NONRESUM_KBUF_PA !=
              offsetof(struct trap_per_cpu, nonresum_kernel_buf_pa)) ||
             (TRAP_PER_CPU_FAULT_INFO !=
-             offsetof(struct trap_per_cpu, fault_info)))
+             offsetof(struct trap_per_cpu, fault_info)) ||
+            (TRAP_PER_CPU_CPU_MONDO_BLOCK_PA !=
+             offsetof(struct trap_per_cpu, cpu_mondo_block_pa)) ||
+            (TRAP_PER_CPU_CPU_LIST_PA !=
+             offsetof(struct trap_per_cpu, cpu_list_pa)))
                 trap_per_cpu_offsets_are_bolixed_dave();
 
         /* Attach to the address space of init_task.  On SMP we
diff --git a/include/asm-sparc64/cpudata.h b/include/asm-sparc64/cpudata.h
index 7f0a74ec47f6..338b0ca5b519 100644
--- a/include/asm-sparc64/cpudata.h
+++ b/include/asm-sparc64/cpudata.h
@@ -65,8 +65,16 @@ struct trap_per_cpu {
         unsigned long           nonresum_mondo_pa;
         unsigned long           nonresum_kernel_buf_pa;
 
-/* Dcache lines 3 and 4: Hypervisor Fault Status */
+/* Dcache lines 3, 4, 5, and 6: Hypervisor Fault Status */
         struct hv_fault_status  fault_info;
+
+/* Dcache line 7: Physical addresses of CPU send mondo block and CPU list.  */
+        unsigned long           cpu_mondo_block_pa;
+        unsigned long           cpu_list_pa;
+        unsigned long           __pad1[2];
+
+/* Dcache line 8: Unused, needed to keep trap_block a power-of-2 in size.  */
+        unsigned long           __pad2[4];
 } __attribute__((aligned(64)));
 extern struct trap_per_cpu trap_block[NR_CPUS];
 extern void init_cur_cpu_trap(void);
@@ -108,8 +116,10 @@ extern struct sun4v_2insn_patch_entry __sun4v_2insn_patch,
 #define TRAP_PER_CPU_NONRESUM_MONDO_PA  0x30
 #define TRAP_PER_CPU_NONRESUM_KBUF_PA   0x38
 #define TRAP_PER_CPU_FAULT_INFO         0x40
+#define TRAP_PER_CPU_CPU_MONDO_BLOCK_PA 0xc0
+#define TRAP_PER_CPU_CPU_LIST_PA        0xc8
 
-#define TRAP_BLOCK_SZ_SHIFT             7
+#define TRAP_BLOCK_SZ_SHIFT             8
 
 #include <asm/scratchpad.h>